Answer:

It is usually apoplexy.

It is the result of a rupture of one of the blood vessels of the brain, and may be caused by overfeeding, or too stimulating food, or injuries.

It may also result from violent exertion or straining in laying eggs. Hens are often found dead in the nest or under the perches from this cause.

There is no remedy, as the bird dies before the trouble is discovered.